Ed Sheeran says Pharrell Williams encouraged him to venture outside his "comfort zone" on his new album.

The singer-songwriter is due to release his second record 'x' on June 23 and Williams was enlisted to work on the single 'Sing'.

However, Sheeran told the Daily Star that he initially felt uncomfortable working with the 'Happy' hitmaker because he wanted to take the Brit away from his usual sound.

He said: "He is soul. I felt uncomfortable at first but it was him pushing me out of my comfort zone because we did two other songs that were very similar to the style I usually do.

“He was saying: ‘There’s no point having a session with me if you don’t come over to my side a little'. I had a clear idea what I wanted and that was the problem. I was becoming predictable.”

Sheeran unveiled 'Sing' on Monday (April 7) and it is due to be formally released on June 1.

Listen to Ed Sheeran's 'Sing' below: